title: The influence of extracellular hydrogen on the metabolism of Bacteroides ruminicola, Anaerovibrio lipolytica and Selenomonas ruminantium.
abstract: Strains of three anaerobic rumen bacteria, Bacteroides ruminicola, Anaerovibrio lipolytica and Selenomonas ruminantium, were able to use extracellular H2 to reduce fumarate to succinate. Each bacterium possessed membrane-bound hydrogenase and fumarate reductase activity. Membrane-bound cytochrome b was reducible by H2 and oxidizable by fumarate in each bacterium. The apparent Km values for hydrogen of the hydrogenases were 4 . 5 x 10(-6) M, 1 . 4 x 10(-5) M and 4 . 4 x 10(-5) M for B. ruminicola, A. lipolytica and S. ruminantium, respectively. The apparent Km values for fumarate of the fumarate reductases were approximately 1 . 0 x 10(-4) M for each bacterium.
mesh_terms: D000693:Anaerobiosis; D001419:Bacteria / Q000378:metabolism*; D001439:Bacteroides / Q000378:metabolism*; D003580:Cytochromes / Q000378:metabolism; D005285:Fermentation; D005650:Fumarates / Q000378:metabolism; D006859:Hydrogen / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism; D013386:Succinates / Q000378:metabolism; D014733:Vibrio / Q000378:metabolism*
chemical_list: D003580:Cytochromes; D005650:Fumarates; D013386:Succinates; D009243:NAD; D006859:Hydrogen; D010088:Oxidoreductases